The Centers for Medicare and Medicaid Services (CMS) has finalized a rule expanding the qualifying life events that allow individuals and families to enroll in Affordable Care Act (ACA) Marketplace health insurance outside of the annual Open Enrollment Period. The rule addresses gaps that left some consumers without a timely pathway to coverage following significant life changes, and builds on a series of enrollment access expansions CMS has made since 2021.
What Is a Special Enrollment Period?
The ACA's Open Enrollment Period -- which runs November 1 through January 15 in most states using the federal HealthCare.gov platform -- is the primary window for individuals and families to select or change Marketplace health plans. Outside that window, enrollment is generally limited to people who experience a qualifying life event that triggers a Special Enrollment Period (SEP). Classic SEP triggers include losing job-based health coverage, getting married, having or adopting a child, or permanently moving to a new coverage area.
A SEP typically gives eligible individuals 60 days from the qualifying event to enroll in a new plan. Missing that window has historically meant waiting until the next Open Enrollment Period, leaving some people uninsured for months during the gap.
What the 2026 Rule Changes
The CMS final rule expands the qualifying events in several meaningful ways. Income changes that cause someone to newly qualify for premium tax credits now trigger a SEP -- previously, income changes alone did not open an enrollment window unless they crossed the Medicaid eligibility threshold. This change creates a pathway for people whose financial circumstances shift mid-year to access subsidized coverage they could not previously afford.
The rule also expands SEP access for people who lose coverage from certain non-traditional sources, including short-term limited-duration health plans that lapse or are terminated by the insurer. Previously, loss of short-term coverage did not trigger a SEP because short-term plans are not considered minimum essential coverage under the ACA. The new rule provides a pathway for affected consumers who lose short-term coverage and need to transition to an ACA-compliant plan.
Additionally, the rule addresses coverage gaps created when consumers are caught in bureaucratic delays -- specifically, individuals who applied for Medicaid or CHIP and were denied or experienced a lengthy processing delay now have an explicit SEP pathway to Marketplace coverage while their eligibility determinations are resolved.
Context: Premium Tax Credit Enhancement
The expanded SEP provisions take on added importance given the current premium tax credit environment. Enhanced credits established under the American Rescue Plan Act and extended through the Inflation Reduction Act have significantly reduced net premiums for many Marketplace enrollees -- in some cases to zero for lower-income households. CMS data shows record Marketplace enrollment in 2025 and 2026, driven largely by the enhanced credit availability. Expanding SEP access ensures that more consumers can take advantage of those credits when their circumstances change mid-year rather than waiting for the next open enrollment window.
How to Use a Special Enrollment Period
To enroll through an SEP, consumers must document their qualifying event. For loss of job-based coverage, this typically means a letter from the former employer or plan confirming the coverage end date. For income changes, documentation may include a pay stub, employer letter, or tax return. Applications through HealthCare.gov or a state-based Marketplace walk through the required documentation for each SEP type.
Consumers who believe they qualify for an SEP should act promptly -- the 60-day window from the qualifying event is firm in most cases, and late applications are not accepted outside the window. Use our Health Insurance Calculator to estimate your premium and subsidy amount, and see our ACA Subsidies guide for more on how premium tax credits work.